Hamson roxendorff



No. 6l9,507. Pater lted Feb. l4, I899.

' A. F. A. RDXENDDBFF.

DRIVING MECHANISM FOR BICYCLES.

(Application filed Dec/24 1897.)

(No Model.)

- uwutozx Fa, oxen 80% @Q L Gamm UNITED STATES PATENT OFFICE.

AXEL FREDRIK ABRAHAMSON ROXENDORFF, OF STOOKHOLM, SWEDEN,

DRIVING MECHANISM FOR BICYCLES.

SPECIFICATION formingpart of Letters Patent No. 619,507, dated February 14, 1899.

Application filed December 24, 1897. Serial No. 663,386. (No model.)

To all whom it may concern:

Be it known that I, AXEL FREDRIK ABRA- HAMSON ROXENDORFF, mechanical engineer, a subject of the King of Sweden and Norway, and a resident of Stockholm, in the Kingdom of Sweden, have invented certain new and useful Improvements in Driving Mechanism for Varying the Exertion of Power in Bicycles and other Vehicles, (patented by me in the following countries: Germany, No. 94,356, dated October 31, 1896; Great Britain, No. 6,339, dated March 10, 1897; Austria, No. 47/4955, dated October 17,1897; Belgium, No. 127,152, dated March 22, 1897; Italy, Vol. LXXXVII, No. 141, dated March 31, 1897, and France, No.263,967,dated February 11, 1897,) of which the following is a specification, reference being had therein to the accompanying draw- 1ngs.

This invention has for its purpose to secure to me the exclusive right to certain constructions of bicycles and other vehicles in which the driving mechanism consists of oscillating treadles to which are secured chains or other driving means having one end fastened to a friction or ratchet coupling acting on the hub of the driving-wheel, one such coupling being located on each side, while the other end of the chain, &c., is fastened to the treadle.

The fulcrum of treadles can slide along a circular bow B, either below the center of the driving-wheel, Fig. 1, or above said center, Fig. 2. The fulcrum of the treadles can be raised or lowered by means of the rods It, connected to a ring H, which can slide on the upmost frame-tube and which is provided with an eccentric or the like for firmly holding the ring H in position at any desired point on said tube. In the mechanism shown, Fig. 1, motion is communicated to the hub of the driving-wheel by depressing the one treadle, the other treadle being simultaneously lifted by a special mechanism. In the mechanism shown in Fig. 2 motion is communicated to the hub of the driving-wheel by lifting the one treadle, this being attained by depressing the other treadle,as the treadles are connected to one another by means of a rope or chain c', running over a block Z, attached to the frame.

If the fulcrum of the treadles in both cases be in the position N and if the treadle be acted upon by a force b, a tension a will be effected in the chain D. If the fulcrum of the treadles be moved to the position M, a tension at is effected in the chain, this tension 0. being considerably greater than the tension at because the angle between the chain and the treadle has been reduced, (see the parallelogram of forces on the drawings.)

The center of the bow B coincides with the points of attachment of the chains to the treadles when these latter are in their middle position, in consequence of which said middle position is the same no matter where the fulcrum of the treadles is situated on the bow B.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a bicycle, or similar vehicle, the combination with the driving-wheel, the hub thereof and the axle, of the coupling adapted to engage with said hub, the chain connected with said coupling, the oscillating treadle with which said chain is also connected and the adjustable fulcrum with which said treadle is pivotally connected, and said fulcrum and treadle being adjustable with respect to the center of the driving-wheel, substantially as described.

2. In a bicycle or similar vehicle, the combination with the driving-wheel, the hub, the axle and the coupling engaging with said hub, of the curved and adjustable fulcrum-bar, the oscillating treadle pivoted thereto and the chain connecting said treadle and coupling, the construction being such that the fulcrum-bar and treadle are adjustable with respect to the center of the driving-wheel, substantially as described.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

AXEL FREDRIK ABRAHAMSON ROXENDORFF.

Witnesses:

E. HERMANSSON, HANS B. OHLSSON. 

